Crossrail will, on start, allow use of Oystercards, but that is over 12 months away & will only allow use on Crossrail trains, not GWR▸ (Great Western Railway).
Anything else I think is probably in the next GWR franchise
Anything else I think is probably in the next GWR franchise
Cross rail is indeed a long time away, and would be especially useful given that my workplace is next to Farringdon station